Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F2/00—Processes of polymerisation
  • C08F2/12—Polymerisation in non-solvents
  • C08F2/16—Aqueous medium
  • C08F2/22—Emulsion polymerisation

Definitions

• the present invention relates to aqueous polymer dispersions of extremely fine size, and in particular dispersions based on acrylic material, having an average particle size of less than 60 nm. More specifically, the aqueous polymer dispersions of the present invention are carried out by incremental addition of monomer and initiator solutions to an aqueous solution containing at least one emulsifier maintained in a minor amount. To date, there are many latex emulsions. However, the particle sizes of such latexes are generally large, for example 120 nm and larger.
• Latexes generally have a particle size greater than 100 nm.
• United States patent US-A 4,228,047 to Pippin et al. relates to an aqueous coating composition comprising a copolymer of at least 95% by weight by weight of vinyl acetate and at least 0.1% by weight of maleic anhydride, which would have improved compatibility with a binder based starch.
• Belgian patent BE-A 812139 to DeSoto, Inc. relates to opaque coatings obtained from a latex consisting of an aqueous suspension of small and large resin particles, the large particles having a Tg lower than that of small and having an average diameter which is more than twice that of the small particles, the latter forming 20 to 65% by weight of the total particles.
• the particles are such that neither large nor small can, by themselves, combine when the latex is dried, to form a non-cellular film.
• the small particles actually give a powder under such conditions.
• the small particles are preferably polystyrene and the large particles are a vinyl acetate and ester copolymer of an alkanol of 4 to 18 carbon atoms and of an unsaturated carboxylic acid.
• the composition contains a minimal amount of solvent and quickly gives an opaque coating of low porosity after drying. It can be used for lipstick, pencils, etc.
• the mixing is carried out at a temperature suitable for dispersing the polymer into particles of size less than 10 nm.
• the dispersions obtained have very small particle sizes, so that they can be spread in a thin layer on aluminum substrates to give coatings free of voids, and as as flocculants to separate suspended matter from water.
• N, N-dimethylaminoethyl methacrylate is a suitable comonomer.
• Japanese patent application JP-A 52-123478 to Kurraray relates to compositions prepared by the emulsion polymerization of unsaturated monomers in the presence of a protective colloid which is prepared by cleaving copolymers dissolved in water in the presence of free radicals and by heating.
• the compound contains units of maleinimide and / or N-substituted maleinimide and units of alpha-olefin as essential components of the main chain.
• An article by Jayakrishnan and Shah, Journal of Polymer Science, Polymer Letters, 22, p. 31: 1984 relates to a mass polymerization of microemulsion particles of polystyrene or methyl methacrylate having a number average size of about 10 to about 60 nm, using sodium dihexylsulfosuccinate and block copolymers of ethylene oxide-oxide propylene as blended emulsifiers, and an oil-soluble initiator such as benzoyl peroxide.
• the weight ratio of the emulsifier to the monomer was approximately one to one and the microemulsion could not be diluted with water.
• Canadian patent application CA-A 2,013,318, to BF Goodrich relates to a process for producing aqueous polymeric microemulsions of very fine size.
• the method uses the incremental addition of a monomer feed solution in a aqueous solution including one or more emulsifying agents and one or more water-soluble or redox initiators. While this method can be used to prepare such microemulsions, it is deficient in that the emulsion tends to discolor and it is extremely difficult to obtain emulsions having a narrow particle size range profile.
• European patent application EP-A 0 429 207 to Rohm & Haas, relates to a process for treating or coating a substrate with an aqueous composition.
• the coating composition is an aqueous dispersion of copolymer particles having mutually incompatible phases and having an average particle size of about 20 to about 70 nm.
• the dispersion is prepared by emulsion polymerization techniques.
• the particles are of a core / shell morphology where the core has a Tg of at least 45 ° C and the shell has a Tg of less than 35 ° C.
• a process has now been found for preparing latex emulsions of ultrafine size which do not discolour, have a resized grain size, are easily reproducible, and which uses a minimum quantity of surfactant.
• the process is in particular characterized by the incremental introduction of monomers and initiators into an aqueous reaction medium so that the ionicity of the reaction medium remains constant.
• the process uses monomers derived from acrylic acids and esters, and gives ultrafine size latexes having an average particle size of less than 50 nm.
• Another embodiment of the present invention comprises the aqueous dispersion capable of being prepared by the above method.
• Ultrafine size polymer latex is stable to coagulation and can therefore be diluted with water.
• the polymer particles have several physical attributes such as good film formation, good penetration into porous substrates, very high specific surface area to volume ratio, monomodality and the like.
• the new dispersions can be used in the manufacture of wood preservatives, polymer and metallic coatings, adhesives, water-proofing chemicals, textile finishes, agrochemicals, pharmaceuticals, chemicals for oil fields, inks, stationery, rheology modifiers, cosmetics, ultraviolet light scattering agents, in biomedical and immunoassay applications.
• An object of the present invention is to produce a latex emulsion of ultrafine size which does not discolour, has a narrow particle size, is easily prepared, and which uses a minimum quantity of surfactant.
• a further object of the present invention is to provide an ultrafine size latex emulsion which is stable to coagulation, is well film-forming, penetrates well in porous substrates, has a very high surface area to volume ratio and a single mode.
• Ultrafine size latexes are prepared by incrementally adding one or more ethylenically unsaturated monomers capable of polymerizing in an aqueous environment, and incrementally adding a polymerization initiator to a reactor containing water and one or more surfactants, then leaving polymerizing the ethylenically unsaturated monomer (s) so that the average particle size of said polymerized monomers is less than 100 nm.
• incremental addition defines any form of addition of a small amount of total monomer and / or initiator to the aqueous solution over an extended period of time, until all of the monomer solutions and initiator is added. This includes cyclic additions, interrupted additions, combinations thereof, and the like. Preferably, the addition of the monomer and the initiator is continuous and at a constant rate over a period of time. Any ethylenically unsaturated monomer which is capable of polymerizing in an aqueous environment as a starting material can be chosen.
• a particularly preferred monomer is any of the following monomers: (meth) acrylic acids and esters, acrylonitrile, styrene, divinylbenzene, vinyl acetate, ethylenically unsaturated carboxylic acids, acrylamide, methacrylamide, vinylidene chloride, butadiene and vinyl chloride.
• the solid products of the dispersion which are produced can take the form of homopolymers (i.e., only one type of monomer selected) or copolymers (i.e., mixtures of two are chosen types of monomer or more; this specifically includes terpolymers and polymers derived from four or more monomers).
• the use of acrylic acids and esters is most preferred.
• the acrylic polymers of the present invention are obtained from one or more acrylate monomers corresponding to the formula: where R1 is preferably hydrogen or an alkyl group having from 1 to 4 carbon atoms and R2 is an aliphatic group having from 1 to 20 carbon atoms. In the most preferred embodiments, R1 represents a methyl group and R2 is an alkyl group having 1 to 20 carbon atoms.
• Specifically useful monomers falling within the scope of formula (I) include methyl methacrylate, ethyl acrylate, butyl acrylate, methacrylic acid, acrylic acid and mixtures thereof.
• the amount of acrylic monomer typically ranges from about 30 to about 99% of the total amount of monomers, the amounts ranging from about 50 to about 90% being more preferred, and amounts ranging from about 60 to about 80% being the most preferred.
• the copolymer can include up to 60% by weight of acid. This is much higher than the systems of the prior art and allows latexes to be particularly useful in textile applications, as the materials obtained are easier to dissolve in a base.
• the separate monomers can be introduced into the aqueous reaction medium from the same feed container or from different containers.
• the polymers produced may be crosslinked. This is accomplished by adding one or more crosslinking agents to the reaction medium.
• crosslinking agent examples include monofunctional compounds such as N-alkylolamides of the formula where R3 is an alkyl group having from 1 to 10 carbon atoms, preferably from 1 to 4 carbon atoms; R4 is hydrogen or an alkyl group having from 1 to 10 carbon atoms, preferably from 1 to 4 carbon atoms; and R5 is hydrogen or an alkyl group having 1 to 4 carbon atoms.
• crosslinking agents include N-methylolacrylamide, N-ethanolacrylamide, N-propanolacrylamide, N-methylolmaleimide, N-ethylolmaleamide, N-methylolmaleamic acid, esters of N- acid methylolmaleamic, N-alkylolamides of vinyl aromatic acids such as N-methylol-p-vinyl-benzamide, and the like.
• Another useful crosslinking agent is N- (isobutoxymethyl) acrylamide.
• difunctional compounds or monomers can also be used as effective crosslinking agents. They include compounds containing two olefinic groups such as divinylbenzene, divinylnaphthalene, divinylcyclohexane, and the like; various diacrylate and dimethacrylate esters of aliphatic diols where the ester moiety has from 1 to 10 carbon atoms, and is preferably an alkyl group when the diol moiety has from 2 to 8 carbon atoms.
• Examples of these materials include ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate and butylene glycol.
• crosslinking agents are described in the Journal of Applied Polymer Science, vol. 34, pp. 2389-2377 (1987) John Wiley & Sons, Inc., in an article entitled "New Cross-Linking Agents for Vinyl Polymers". To the extent necessary, this article is incorporated here for reference.
• the amount of the crosslinking agent, when used, is generally from about 0.05 to about 10% by weight, preferably from about 0.1 to about 5% by weight, and even more so preferred from about 0.1 to about 1.0% by weight based on the total weight of all the monomers added.
• One or more polymerization initiators are also added incrementally to the aqueous reaction medium, preferably a free radical thermal initiator.
• the polymerization initiator can take the form of many known initiators such as azo initiators, peroxides, persulfates and peresters, and can be water soluble or soluble in the monomer.
• the amount of initiator added to the solution typically ranges from about 0.05 to about 2% by weight of the emulsion, with amounts ranging from about 0.1 to about 1.0% by weight being particularly preferred and the amounts ranging from about 0.1 to about 0.5% by weight being the most preferred.
• the free radical initiator added is preferably an azo (azobisnitrile) type initiator (hydro or oil-soluble) such as 2,2'-azobisisobutyronitrile, 2,2'-azobis- (2-methylpropanenitrile), 2, 2'-azobis- (2,4-dimethylpentanenitrile), 2,2'-azobis- (2-methylbutanenitrile), 1,1'-azobis- (cyclohexanecarbonitrile), 2,2'-azobis- (2, 4-dimethyl-4-methoxyvaleronitrile), 2,2'-azobis- (2,4-dimethylvaleronitrile) and 2,2'-azobis- (2-amidinopropane) hydrochloride.
• azo (azobisnitrile) type initiator hydro or oil-soluble
• 2,2'-azobisisobutyronitrile 2,2'-azobis- (2-methylpropanenitrile), 2, 2'-azobis- (2,4-dimethylpentanenitrile),
• free radical initiators which can be chosen include peroxide materials such as benzoyl peroxide, cumene hydroperoxide, hydrogen peroxide, acetyl peroxide, lauroyl peroxide, persulfate materials such as ammonium persulfate, and peresters such as t-butyl peroxypivalate, ⁇ -cumyl peroxypivalate and t-butyl peroctoate.
• peroxide materials such as benzoyl peroxide, cumene hydroperoxide, hydrogen peroxide, acetyl peroxide, lauroyl peroxide, persulfate materials such as ammonium persulfate, and peresters such as t-butyl peroxypivalate, ⁇ -cumyl peroxypivalate and t-butyl peroctoate.
• initiators examples include Wako V-50, Vazo 52, Vazo 64, Vazo 67 and Lupersol 11. These commercial initiators may be included with the monomer charge.
• water-soluble initiators such as peroxides and persulfates
• a conventional initiator charge consisting of ammonium persulfate and representing 1 to 3% by weight of the total volume of water causes the polymer particles to agglomerate throughout the addition of the initiator. It has been found that by maintaining constant ionicity in the reaction mixture, agglomeration can be avoided, giving an emulsion of a more uniform particle size.
• the Ionic resistance of the initiator system is the same as that of the reactor contents at any time during the reaction / introduction of the initiator.
• the same ion balance can be obtained by the careful choice of an initiator soluble in the monomer, of neutral charge, such as the initiator of the azo type marketed, such as VAZO 52 (2,2'-azobis- (2,4 -dimethylvaleronitrile) or VAZO 64 (2,2'-azobisisobutyronitrile) In these cases, the entire amount of initiator is contained in the monomer charge. It is believed that the concept of maintaining constant ionicity in the reaction medium was not used to form ultrafine polymer latexes of uniform size until the present invention. The prior art in the field of ultrafine size latexes describes that the initiator is contained in the aqueous reactor or added in "a single stroke".
• the monomer (s) and the initiator (s) are introduced into an aqueous reaction medium which comprises water and at least one or more emulsifiers.
• the emulsifiers are generally surfactants and can therefore be cationic, nonionic, anionic, amphoteric and similar copolymerizable surfactants, anionics being generally desired.
• the type of emulsifiers used are those which can be used in conventional latex polymerizations.
• a key criterion for choosing a surfactant is its compatibility with the initiator.
• amphoteric surfactants include the alkali metal, alkaline earth metal, ammonium or substituted ammonium salts of alkyl amphocarboxyglycinates and alkyl amphocarboxypropionates, alkyl amphodipropionates, alkyl amphodiacetates, alkyl amphoglycinates and alkyl amphopropionates, where alkyl represents an alkyl group having 6 to 20 carbon atoms.
• amphoteric surfactants include alkyl iminopropionates, alkyl iminodipropionates and alkyl amphopropylsulfonates having between 12 and 18 carbon atoms, alkylbetaines and amidopropylbetaines and alkylsultaines and alkylamidopropylhydroxysultaines where alkyl represents an alkyl group having 6 to 20 carbon atoms.
• the anionic surfactants which can be chosen include any of the known hydrophobes attached to a solubilizing group carboxylate, sulfonate, sulfate or phosphate including the salts.
• the salts can be the sodium, potassium, calcium, magnesium, barium, iron, ammonium and amine salts of such surfactants.
• anionic surfactants include the water-soluble salts of alkyl benzene sulfonates having between 8 and 22 carbon atoms in the alkyl group, alkyl ethersulfates having between 8 and 22 carbon atoms in the alkyl group, the salts of alkali metal, ammonium and alkanolammonium or organic sulfuric reaction products having in their molecular structure an alkyl or alkaryl group containing from 8 to 22 carbon atoms and an ester group of sulfonic or sulfuric acid.
• Linear sodium and potassium alkyl sulfates are preferred. Particular preference is given to the use of sodium lauryl sulfate (sodium dodecyl sulfate).
• anionic surfactant are alkyl benzene sulfonates, in which the alkyl group contains between about 9 and about 15, and more preferably, between about 11 and about 13 carbon atoms in a straight chain configuration or a branched chain, and even more preferably a straight straight chain having an average alkyl group of about 11 carbon atoms.
• mixtures of anionic surfactants can be used, mixtures of sulfonate surfactants and alkyl or alkylaryl sulfates being particularly preferred.
• Such embodiments include a mixture of alkali metal salts, preferably sodium salts, alkyl benzene sulfonates having from about 9 to 15, and preferably between 11 and 13 carbon atoms, with a salt of an alkali metal, preferably sodium, of an alkyl sulfate or of an alkyl ethoxysulfate having 10 to 20, and preferably 12 to 18, carbon atoms and an average ethoxylation of 2 to 4.
• alkali metal salts preferably sodium salts, alkyl benzene sulfonates having from about 9 to 15, and preferably between 11 and 13 carbon atoms
• a salt of an alkali metal preferably sodium, of an alkyl sulfate or of an alkyl ethoxysulfate having 10 to 20, and preferably 12 to 18, carbon atoms and an average ethoxylation of 2 to 4.
• anionic surfactants which can be chosen include linear alkyl benzene sulfonates such as dodecylbenzenesulfonate, decylbenzenesulfonate, undecylbenzenesulfonate, tridecylbenzenesulfonate, nonylbenzenesulfonate and sodium, potassium and ammonium salts, ammonium, triethyl isopropylammonium thereof.
• linear alkyl benzene sulfonates such as dodecylbenzenesulfonate, decylbenzenesulfonate, undecylbenzenesulfonate, tridecylbenzenesulfonate, nonylbenzenesulfonate and sodium, potassium and ammonium salts, ammonium, triethyl isopropylammonium thereof.
• nonionic surfactants examples include ethylene oxide condensates with a hydrophobic moiety which has an average hydrophilic-lipophilic balance (HLB) between about 8 and about 16 and preferably between about 10 and about 12, 5.
• HLB hydrophilic-lipophilic balance
• surfactants include the condensation products of primary or secondary aliphatic alcohols having from about 8 to about 24 carbon atoms, in a straight or branched chain configuration, with from about 2 to about 40, and preferably between about 2 and about 9, moles of ethylene oxide per mole of alcohol.
• Other suitable nonionic surfactants include the condensation products of alkylphenols of about 6 to about 12 carbon atoms with about 3 to about 30, and preferably between about 5 and about 14 moles of ethylene oxide.
• surfactants examples are marketed under the trade names Igepol CO 530, Igepol CO 630, Igepol CO 720 and Igepol CO 730 by Rhône-Poulenc. Still other suitable nonionic surfactants are described in US Patent US-A 3,976,586. To the extent necessary, this patent is expressly incorporated for reference.
• cationic surfactants include cetyltrimethylammonium bromide.
• Other surfactants which may be used include those described in McCutcheons, "Detergents and Emulsifiers", 1978, North American Edition, edited by McCutcheon, MC Publishing Corp., Glen Rock, New Jersey, UESTA., As well as in various subsequent editions. To the extent necessary, this publication is expressly incorporated for reference.
• the amount of surfactant present in the aqueous phase ranges from about 0.5 to about 6.3% by weight of the monomers added. Amounts between about 0.5 and about 3.0% by weight of the total monomers added are more preferred and amounts between about 1.0 and about 3.0% by weight of the total monomers added are most preferred.
• the reaction medium can include between about 0.5 and about 10.0% by weight, added monomers, other optional additives to provide specific functional properties to the final latex.
• additives include plasticizers such as polyethylene glycol, defoamers, pigments, dyes and dyes, antibacterial agents, perfumes, pharmaceuticals, enzymes and other biologically active agents, products agricultural chemicals, ultraviolet active agents, stabilizers and rheology modifiers.
• a semi-continuous or continuous polymerization process is used. This includes the addition of the monomer, the introduction of the crosslinking agent if necessary and incremental initiator solutions in the reactor, which is typically brought to temperatures between about 45 ° C and about 90 ° C and includes water and one or more emulsifiers over a period of time, unlike batch addition.
• the reactor may contain a small amount of monomer before the start of the incremental polymerization, which acts as a "seed". Such a small amount of monomer is generally less than 30% by weight and preferably not more than about 10% by weight of the total monomer used.
• the rate of addition of the monomer is generally controlled by various factors such as the size of the reactor, the increase in exothermic reaction temperature, the cooling capacity of the reactor, and the like, so that the reaction temperature is generally maintained at a specific value or range.
• the amount of emulsifier (s) generally contained in the reactor is generally at least 50 or 60% by weight, preferably at least 70% by weight, more preferably at least 80% by weight, and preferably at least 90% by weight of the total amount of emulsifiers.
• the remaining emulsifier, if any, is introduced with the charge streams of monomer or initiator.
• the reactor can be maintained at temperatures as low as ambient temperatures (10 ° C to 20 °) up to the boiling point of the aqueous solution.
• the reaction pressure is generally atmospheric, but it can be raised if necessary to aid the polymerization.
• the monomer charge and the initiator charge can be the same charge if the initiator is soluble in the monomer.
• the initiator is water-soluble and charged, like ammonium persulfate, it is introduced so that the ionicity in the entire reactor is maintained at a constant. This is typically accomplished by initially transferring a quantity of water from the reactor into the initiator charge to create ionic concentrations which are, both in the feed container and in the reactor, substantially equal.
• the introduction of the initiator solution on an incremental basis provides a concentration of free radicals generally in steady state, throughout the addition of the monomer.
• the average particle size of the polymer is very small.
• particle size is meant the median particle size by volume, measured by photocorrelation spectroscopy.
• the polymer latexes produced according to the present invention have a very small volume average particle size of 100 nm or less, the preferred average particle sizes being between about 1 and about 60 nm, more preferred between about 5 and about 40 nm, even more preferred between about 10 and about 30 nm, and ideally between about 10 and about 20 nm. In general, any of the above particle size ranges can be obtained depending on the specific end properties desired.
• the range of the particle size range produced is limited.
• the standard deviation for each latex of desired size is not more than 4 nm.
• the above process gives a polymer latex which is stable to coagulation insofar as it can be diluted with water without the appearance of coagulation.
• the solid content of the latex is relatively high, such as from about 5% to about 55% by weight, desirably from about 15% to about 50% by weight, more preferably from about 20 to about 40% by weight, and most preferably from about 25 to about 35% by weight, based on the total weight of the aqueous polymer latex.
• the properties of the polymer latex largely depend on the monomers chosen for the polymerization.
• the glass transition temperature of the polymers can range from about -54 ° C to over 130 ° C.
• the polymeric latexes of the present invention due to their extremely fine size, are useful in many applications such as wood preservatives, polymeric and metallic coatings, adhesives, water-proofing chemicals , textile finishes, agricultural chemicals, pharmaceuticals, chemicals for oil fields, inks, stationery, rheology modifiers, cosmetics, personal care products, ultraviolet light scattering agents, sunscreens, and biomedical and immunoassay applications. Although they are latex in structure, they often approach solution type properties. In addition, they can be used alone or in combination with other materials, such as larger particle size emulsions, to provide products with specifically designed uses.
• An aqueous polymeric methyl methacrylate latex is prepared as follows: 100 parts per hundred (ppc) of methyl methacrylate are mixed with 0.5 ppc of Vazo 52, a thermal initiator (2,2'-azobis- (2,4 -dimethylvaleronitrile)) soluble in methyl methacrylate.
• This monomer / initiator solution is introduced regularly over 3 hours into a 1 liter glass reactor which contains 185 ppc of water and 3 ppc of sodium dodecylsulfate. The reactor is maintained at 85 ° C and constantly stirred. At the end of the addition of the monomer, the reactor is maintained at 85 ° C for an additional 1 hour.
• reaction mixture is then brought to an almost complete conversion by treatment with 0.015 ppc of t-butyl hydroperoxide and 0.015 ppc of sodium metabisulfite, at a temperature of 62 ° C.
• This synthesis results in an aqueous polymer latex containing 35% by weight of solid products.
• the average particle size, measured by a Niacomp 370A, is 14 nm.
• This polymer latex is translucent due to the small particle size of the latex particles.
• the latex is blue in color and has a Tg of around 105 ° C.
• An aqueous polymer latex of butyl acrylate, methyl methacrylate and methacrylic acid is prepared using the same process as in Example 1.
• the composition of the monomer / initiator solution is 65 ppc of butyl acrylate, 25 ppc of methacrylic acid, 10 ppc of methyl methacrylate and 1 ppc of VAZO-64 (2,2'-azobisisobutyronitrile).
• This process gives a latex at 25% by weight of total solid products and an average particle size measured by volume of 14 nm.
• the latex is transparent, blue in color, and has a Tg of around -5 ° C.
• An aqueous polymer latex of styrene, butyl acrylate and methacrylic acid is prepared as follows: 65 ppc of butyl acrylate, 25 ppc of methacrylic acid and 10 ppc of styrene are carefully mixed together to form a solution of charge.
• 0.25 ppc of ammonium peroxydisulfate is added to 65 ppc of water.
• 3 ppc of sodium dodecyl sulfate is added to 244 ppc of water and the mixture is heated to 85 ° C. with continuous stirring.
• the reason for the preparation of the separated aqueous initiator solution is to allow constant ionicity in the reactor throughout the synthesis procedure.
• a solution containing 0.1 ppc of sodium metabisulfite dissolved in 24 ppc of water is then introduced into the reaction mixture over an interval of 1 ⁇ 2 hour. The temperature is maintained for 1 hour and the reaction mixture is then cooled to room temperature and is filtered. A transparent blue latex is obtained having a solids content of 23.3% and an average particle size of approximately 14 nm.
• Table 1 Sample Particle size Penetration AT ⁇ 30 nm minimal B ⁇ 30 nm minimal VS 90 nm slight D 100 nm appreciable E 150 nm important
• the minimum penetration observed when using the materials of the invention demonstrates that the latexes of smaller particle size penetrate the wood better than conventional latexes. Consequently, the materials of the invention form significantly better protective coatings for wood than commercial materials.
• the penetration capacity depends a lot on the humidification capacity. If a product does not moisten a surface well, it will have little chance of penetrating that surface. The higher surface tension of sample A, the sample of the invention, gives this product a clear disadvantage in penetration studies.
• the latex of Example 6 is compared with the commercial products Permaloid 150 and Permaloid 172, both manufactured by Rhône-Poulenc for use as textile finishes. All samples are evaluated at 7% concentrations and applied to polyester filament fibers with a laboratory gluing machine. The abrasion resistance of the latex of sample 6 is approximately equal to that of Permaloid 150 and Permaloid 172.
• the advantage provided by the use of the latex of the invention is the absence of neutralization before application .
• Conventional primers, such as Permaloid 150 and Permaloid 172 are applied in the form of polymer solutions prepared by the alkali-induced solubilization of a conventional latex polymer.
• the textile finishes based on ultrafine latex of the invention are applied directly to the fiber without neutralization. This eliminates the need for alkali and the control of ammonia evolution, normally associated with the finishing of filament fibers, and therefore provides significant advantages over commercially available materials.

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